Reloaded 308 Won’t Fit Ruger American II

DMW1116

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I’ve been dozing and shooting 308 Winchester in my AR10 for a couple of years now with minimal trouble in terms of chambering. My son bought a 308 Ruger American II so I thought I’d test a few in his rifle. The dozing die is bottomed out on the shell holder so I can’t really go any lower that way. When I try to chamber the reloaded rounds I have difficulty locking the bolt closed. Any idea what causes this? I’m loading 168 grain Amax, 168 grain Speer, and 150 grain Hornady FMJ, all to 2.795” - 2.800” COAL. Cases are trimmed when they exceed the max of 2.015”. Generally they run between 2.007” and 2.010”. My case trimmer takes them down to 2.006” - 2.007”.
 
Dozing die? Sounds as if it's sleeping on the job. How do factory rounds chamber?
If you have a comparator, I'd check the shoulder on the factory ammo vs the reloads. I'd also clean the chamber thoroughly, make up a dummy reload, mark it up with the Sharpie, and chamber it it as it will give some answers on where the brass is having issues.

Chances are the chamber in the Ruger is a little short at the shoulder and even bottoming out the sizing die to cam over isn't pushing the shoulder back enough. If that's the case, you have 4 options. Call Ruger, explain the them what is happening and they may have you send it in. Option 2 is find a smith with a 308 reamer and have them take just a blonde one out of the chamber. This really easy, is done by hand and takes 5 minutes. Option 3 is remove just a little bit of material from you shell holder to allow for more shoulder bump. Option 4? Shoot factory ammo which sucks.
 
die is bottomed out on the shell holder so I can’t really go any lower that way. When I try to chamber the reloaded rounds I have difficulty locking the bolt closed.

I would start with just the case and set the die so you can get the bolt closed.


If you can't do that, then focus your efforts on that step. No reason to proceed to any further steps if the bolt can't close on a sized case. The reason I say this is that I have seen several Ruger bolt rifles that do not have enough lead to the rifling. So the case can be sized perfect and the finished round not allow the bolt to close. You can check and see if that is your problem by coloring the bullet with a sharpie.

Note the center bullet and the marks where the rifling contact the bullet at factory OAL, even the much deeper seated bullet on the left is still contacting the rifling.

6CD52E05-602A-44AA-9C45-C4A16C158818.jpeg

You can size the case as under as you want and still not get the bolt to close with that bullet at that length. Why I would suggest starting at step 1 vs the final product to find where the problem actually is vs just guess.
 
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I’ve been dozing and shooting 308 Winchester in my AR10 for a couple of years now with minimal trouble in terms of chambering. My son bought a 308 Ruger American II so I thought I’d test a few in his rifle. The dozing die is bottomed out on the shell holder so I can’t really go any lower that way. When I try to chamber the reloaded rounds I have difficulty locking the bolt closed. Any idea what causes this? I’m loading 168 grain Amax, 168 grain Speer, and 150 grain Hornady FMJ, all to 2.795” - 2.800” COAL. Cases are trimmed when they exceed the max of 2.015”. Generally they run between 2.007” and 2.010”. My case trimmer takes them down to 2.006” - 2.007”.

Have you tried chambering just a piece of sized brass? If good your bullet may be contacting the rifling. If not you can add a shim between the brass and shell holder and size it some more. Once you know how much shim is needed you can have the bottom the die turned off to length.
 
Won't bother repeating the good advice already give, but would only add that I have found it very helpful on bolt action rifles to learn to strip the bolt so you can see and feel the bolt close on sized brass or a seated bullet. That and sharpies on both. You need to be able to "map" the chamber and a stripped bolt helps you do that.
 
Every gun and every chamber is unique. The answer has already been stated. You have two possible issues, assuming the chamber is clean. The first is that you may need to bump the shoulder back a little. The second is that you may need to seat the bullet a little deeper so it is not contacting the rifling. As suggested, take measurements to confirm which, or both, of these issues are causing the problem. Then, rework your load as the dimensions have changed and you may be increasing pressure.
 
Might try a small-base sizing die. While such are generally associated with semi-autos rather than bolt-actions, it could be that the Ruger has a tighter chamber than the AR. I don't know Ruger's current practice, but years ago they were known to use their reamers too long, resulting in tight or even egg-shaped chambers from worn reamers. SB sizing dies are widely available and inexpensive.
 
I would shoot factory in your new gun and compare dimensions vs what comes out of your sizing die. The base on cases shot in semi or full autos expand sometimes making chambering difficult. If the base is to big you are better off using brass only shot in that rifle vise fighting the issue.
 
FWIW those rounds above in my post are factory rounds, that didn't fit a new Ruger American. A trip back to them didn't help it either. https://www.thehighroad.org/index.php?threads/centerfire-ruger-american-owners.887337/

The video linked in the post shows how to set the size die without the need of measuring tools, using the rifles chamber as a go/no go gauge. Using that method the case may or may not fit other rifles so chambered but you are sizing them for the rifle they are intended for.
 
I have a Finnwolf 308 with a very tight chamber. It only chambers Federal factory rounds. Even resizing new brass in an RCBS small base die isn't good enough. If you've ever seen the diagrams of the insides of a Finnwolf, you'll understand why I've not run a reamer into it. Sometimes it is better to let sleeping dogs lie.
 
I would start with just the case and set the die so you can get the bolt closed.

Further... and I've mentioned this in previous threads, because it got me when I started loading .308 for my M1a...

Make sure you are setting the sizing die with a case rammed up in the die... not just static (no load) set. Press flex, and necessary loose tolerances between the components mean that while you may be tapping the top of the shellholder without a case... there may very well be room between the shellholder and the sizing die (asleep or not...) when it is under a load (case rammed into the die.) It's not very much... but it may be enough to get you where you need to be. It was for me. I found out later I had the same problem with my very heavy .348WCF brass when I was sizing it on my little RS3 press years ago.
 
Also... FWIW... my brother has a .308 Ruger American of some sort, and my generic .308 reloads (made for my Savage 10TAC, but will fit any of my .308 rifles) fit just fine. You may very well have a tight chamber, or there is something else going on. As was suggested... clean that chamber, check your sizer as I mentioned, and just try a sized cartridge case first.

g8XLRB6l.jpg
 
When Fred Huntington ran RCBS, in certain calibers offered in semi-autos they made dies, small-base dies, "ultra-small-base" dies, and tightest of all, "BAR" dies.
 
Factory ammo chambers easier. My reloads chamber but it takes a bit more effort. The cases are scratched too. I plan to strip the bolt and go from there as described above.

The die is already at the top and touching the shell holder. I couldn’t get the case more into the die without shaving down the shell holder or shimming the case in the shell holder, which I may try or may even be necessary.
 
Factory ammo chambers easier. My reloads chamber but it takes a bit more effort. The cases are scratched too. I plan to strip the bolt and go from there as described above.

The die is already at the top and touching the shell holder. I couldn’t get the case more into the die without shaving down the shell holder or shimming the case in the shell holder, which I may try or may even be necessary.
Where are the scratches
 
The Americans I've been messing with shoot really well because of a nice tight chamber. .223 and X39. Strip the bolt , why. Full length resize and go on.
My long time fav bolt action rounds wouldn't fit a new autoloader recently. You never know.
 
You have a combination of tolerances that are stacking up against you .
Your rifle has a small chamber , your sizing die is on the large side of the tolerances ...
and you are probably using once fired brass from another rifle .

Several things to try ... Small Base sizing die or try a thinner shell holder ... not all shell holders are the same thickness ... or grind your shell holder thinner so the sizer can size it down farther .
I would buy some brand new brass cases and keep them seperate from the other rifles .
Good Luck and Load safe ,
Gary
 
These are mostly either range pickups or from a batch of Federal brass I traded for here. Either me or my son need to run a box or two through it and the see if those fit better after sizing.
 
Factory ammo chambers easier. My reloads chamber but it takes a bit more effort. The cases are scratched too. I plan to strip the bolt and go from there as described above.

The die is already at the top and touching the shell holder. I couldn’t get the case more into the die without shaving down the shell holder or shimming the case in the shell holder, which I may try or may even be necessary.
Sometimes changing shell holders is enough to make a difference. Either way, I highly recommend grinding a new shell holder, not the one you know works for your existing chambers.

Try a different brand. Easier to keep track of that way.
 
Sometimes changing shell holders is enough to make a difference. Either way, I highly recommend grinding a new shell holder, not the one you know works for your existing chambers.

Try a different brand. Easier to keep track of that way.
I agree a different brand or matching the brand of the die. Grinding gets ugly
 
I have experience with 3 different Ruger Americans in 308. All 1st gen rifles but they all had tight chambers. I had no trouble shooting factory loads in them, but some handloads I had would work fine in other rifles, but would be a tight fit, or even a no-fit with the Ruger. I don't necessarily see it as a problem, just a quirk with the Ruger and may be part of the reason they shoot so well.
 
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